CREATE TRIGGER ad_tasks_1
AFTER DELETE ON
    tasks
FOR EACH ROW
BEGIN
    SELECT debug(
        OLD.id,
        OLD.status_id
    );

    DELETE FROM
        tasks_tomerge
    WHERE
        task_id = OLD.id
    ;

    DELETE FROM
        updates
    WHERE
        id = (
            SELECT
                first_update_id
            FROM
                topics
            WHERE
                id = OLD.id
        )
    ;

END;